Unfortunately, Kary Mullis passed away on 7 august 2019, only a few months before his test turned into the one and only instrument to justify the declaration of the pandemic that changed the world. We will never know what he would say about this specific use of his invention. What we do know, is (again) what he said about the PCR test itself:
“With PCR, if you do it well, you can find almost anything in anybody.”